Considerable research and related diagnosis has been undertaken in this field of healthcare. In order to facilitate reference to prior art developments and procedures, journal articles are listed at the end of this specification and are hereinafter referenced by number.
Breast cancer is a leading cause of mortality and morbidity among women (1-4). One of the priorities in breast cancer research is the discovery of new biochemical markers which could be used for diagnosis, prognosis and monitoring (4, 5). Breast cancer is one of a few cancers that is dependent on steroid hormones and their receptors. Currently, estrogen and progesterone receptor analysis is performed routinely as an aid in prognosis and selection of therapy (4-6).
Current indicators for diagnosing and monitoring breast tumors include: tumor size, estrogen receptors, progesterone receptors, age, aneuploidy, mitotic activity and Ki67 (29). The prognostic usefulness of these factors depends on their ability to evaluate which patients with breast cancer require aggressive therapeutic treatment and which patients should be monitored.
Mutation of the p53 tumor suppressor gene is one of the most comDonly known genetic defects in human cancer, including breast cancer and results in mutant protein accumulating to high concentrations. Overexpression of p53 protein expression has been found to be an independent predictor of early disease recurrence (29). The accumulation of p53 protein has been found to be an independent marker of shortened survival (30). The majority of tumors that do not produce mutant p53 protein are estrogen and/or progesterone receptor-positive (14).
Prostate cancer is a leading cause of mortality and morbidity among men (7, 8). Prostate tissue and cancer is also dependent on steroid hormones and therapy that takes advantage of this is currently routinely used (9-10). One of the hallmarks of prostate cancer is the appearance in serum, at elevated concentrations, of a 30-33-KD glycoprotein, prostate specific antigen (PSA) (11). PSA is secreted by the epithelial cells of prostatic tissue and is currently widely used as a tumor marker for diagnosing and monitoring prostatic carcinoma.
Previous iuuunohistochemical studies found no PSA immunoreactivity in breast or other tumors (17) or found occasional PSA immunoreactivity with polyclonal but not monoclonal antibodies, suggesting cross-reactivity effects (18). PSA levels in female serum are undetectable in 90% of women. A few women do have traces of PSA which are thought to be produced in the periurethral glands.
We have surprisingly discovered the presence of PSA in breast tumor.